This invention relates to a radar detecting receiver, and particularly to a receiver which is capable of simultaneously receiving quasi-harmonically related radio frequency signals.
This invention is particularly useful in detecting the presence of radar signals emitted in both the so-called X- and K-bands. The Federal Communications Commission of the United States has established that X-band radar signals be transmitted at 10.525 GHz with a tolerance of .sup..+-. 0.025 GHz, and that K-band radar signals be transmitted at 24.150 GHz with a tolerance of .sup..+-. 0.100 GHz. The most common method presently employed in readily available receivers for detecting these radar signals is a crystal detector; however, these detectors frequently are not sensitive enough to detect a radar signal over a long distance.
It is also possible to use superhetrodyne type receivers for the detection of radio frequency signals in this range, however, the bandwidth required to insure reception of a signal within the frequency limits above specified, and also taking into consideration frequency inaccuracies and drift within the receiver, limits the sensitivity of this type of device.
It is therefore desirable to develope a low cost, highly sensitive radar receiver which is capable of detecting radar signals anywhere within the range of frequencies specified for X- and K-band radar transmitters.